Interstate 40 eastbound in Dickson County is being expanded for a truck climbing ramp on a steep incline.

Chris Gadd, USA TODAY NETWORK – Tennessee

Dickson County work commuters may have noticed in recent months the Interstate 40 construction, and the slower speed limit signs, over a 4-mile stretch near the Dickson-Williamson county line.

The $8 million project is expanding eastbound I-40, allowing for the addition of a truck climbing lane. A steep incline in that area slows some tractor trailer trucks, which can’t reach the speed limit. The sudden reduction in speed can cause bottlenecks, congestion and wrecks. By expanding an additional lane for slower-moving trucks, Tennessee Department of Transportation officials hope to reduce issues from mile marker 179 to 183.

“The area has lot of truck traffic and steep grades, so the truck climbing lane will improve efficiency and safety in the area,” said Kathryn Schulte, spokesperson for Region 3 which includes Middle Tennessee. “Another I-40 truck climbing lane was recently completed in Humphreys and Hickman counties. One is being completed now just west of the Tennessee River bridge, and another is being constructed in Smith County now.”

The truck climbing lane, which was started in December, is part of TDOT’s 25-year long range transportation plan that focuses largely on the I-40 and Interstate 81 corridor. The study was finished in 2008 and detailed the truck climbing lane as well as Expanded Intelligent Transportation Systems for I-40 in Dickson County.

Schulte said the systems are tentatively tapped for construction funding in about two years. The Intelligent Transportation System items include traffic cameras, message boards and sensors.